Some advice on a Chevy Suspension Upgrade

[Asphalt Addict]

Thanks cruising7388, what is the benefit of the larger size?
I used them on the old PW to help with ground clearance along with a 3 inch raise, which helped with off road. I always find a dirt road to explore.

 

[cruising7388]

Here is a link to a post with some pix of the various wheels that we had found at the time, there may be another aluminum one by now but unconfirmed, for stock size tires. The Silverado wheels that are used for the 265 tires are actually only 7.0" wide, which is right on the low end of recommended for that tire size.


http://www.classbforum.com/forums/f8/wheel-offsets-particularly-roadtrek-chevy-1985-2.html#post10407

Oops my mistake. The 245 mounts on a 6.5 inch rim. We ordered 7.0 inch steel wheels for our 265 replacement.rubber which restored the correct factory wheel offset. The 3400 pound rating for this tire is a welcome plus in addition to providing an additional half inch of lift. The only minor thing is that at 60 mph, there is a 2 mph speedometer error compared with our our Garmin GPS mph reading.

 

[booster]

Thanks cruising7388, what is the benefit of the larger size?
I used them on the old PW to help with ground clearance along with a 3 inch raise, which helped with off road. I always find a dirt road to explore.

I think the biggest benefit for me is the improved load carrying capacity of the larger tires, as I am one that likes to have a good amount of "headroom" in relation to the rated capacity.


We were pleasantly surprised that the handling of the van got noticeably better with the change, but I can't attribute how much of the improvement came from the size change and how much came from the tire brand change and the wheel offset change. Those 3 changes do seem to work very well together on the Chevies, especially if you have the wrong offset on the van when you start.

 

[Asphalt Addict]

What brand did you switch to/from?

 

[booster]

What brand did you switch to/from?

We went from the stock Bridgestone V Steel to Michelin MS2.

 

[Asphalt Addict]

Yep. Used to run BF G AT on my old 87 Ford van then switched to Michelin.

 

[cruising7388]

We went from the stock Bridgestone V Steel to Michelin MS2.

I think the MS2 has been replaced with the Defender LTX.

 

[Asphalt Addict]

That's correct. I got mine just a couple of months ago. Defenders.

 

[Bjones7788]

Suspension changes Roadtrek 190 Pop

I just got back from installing Moog 81004 front coil springs and Air Lift 5,000 rear air bags plus Bilstein shocks on the rear, (front Bilsteins were installed earlier) all on our 2013 Roadtrek 190 Polular with 35,000 miles.

First impressions:
1. The sight picture from drivers seat was a more nose up attitude.
2. Seat of the pants feel was more nose up as was the climb into the seat.
3. During a short drive from shop to house there was a prominent sense that the vehicle followed vertical changes along the road with more precision - read stiiffer ride.
4. During that drive fine road roughness was more prominently transferred to the occupant - stiffer ride
3. Don't know how to convey this but there was still an underlying sense of enhanced shock absorber dampening of both - maybe controlled vibration from fine road roughness and minor road up and down movement - I tried to explain, probably did not do very well.

Some measurements, all taken in two different spots using an extended plumb "yard stick" and carpenters level from underside of fender to yard stick all with 50 PSI showing on the air bag remote controller and same water, propane, waste water and load during before and after measurements:
1. Front fender height above ground increased about 4 inches on both sides (This surprised me by being more than I expected)
2. The rear fender height increased by about half of an inch on both sides. (I expected more given 50 PSI in the air bags.)

Followup impressions:
1. Looking at van from the side the front fender LOOKS LOTS HIGHER than my my old recall of that sight picture.
2. I find it odd that the left front was raised a little more than the right front.
3. Our older 2004 Chevy based 190 Popular always was a little lower at the left front than right front when observed by eye ball. I had assumed that the driver weight and water tank under the driver, after 14 years and 200,000 miles had caused the left front springs to sag disproportionately. We shall see if a similar sag seems to occur with the Moog springs on our 2013 over an extended time frame

Aside: I had NAPA "Fleet" front hubs and bearing assemblies installed at the same time as the springs and Air Lift bags, also had NAPA severe duty "Fleet" front rotors and pads installed, plus alignment with specs recommended on this site for our vans after these suspension modifications. OEM front brakes had some "judder", typical compliant about Chevy Roadtreks of that era, and my experience , as well as that of others was that OEM front hub/bearing assemblies had a reputation of early failure for quite a few folks.

Total tab for labor ~$1,000 excluding parts - capable experienced independent local shop that we take our "fleet" to did the work.

More if and when it seems worthwhile to report.

BJ 2004 & 2013 RT 190 Pops
Florida Keys (soon Sun N Fun)
drjones7788@gmail.com

 

[Asphalt Addict]

I'm interested in further results as it wears in. I put in moog springs and air lifts. i put my airlifts at 70lbs. Vehicle appears level, using level inside van. Only got 2.5 inch lift in front.

As far as brake rotors, I replaced OEM with PowerStop rotors from Summit Racing. They have grooves to help cool. Reduced chatter to almost nil.

After the lift I got 2-3mpg reduction. Working on upstream O2 sensor replacement. We'll see if it improves. I also noticed a little float, possibly do to more air undercarriage lifting front end? However, the more I drive the more comfortable the ride.

2008 Chevy Express 3500 Pleasure Way Lexor. Similar to RT 190

Good luck with the results.

 

[booster]

I just got back from installing Moog 81004 front coil springs and Air Lift 5,000 rear air bags plus Bilstein shocks on the rear, (front Bilsteins were installed earlier) all on our 2013 Roadtrek 190 Polular with 35,000 miles.

First impressions:
1. The sight picture from drivers seat was a more nose up attitude.
2. Seat of the pants feel was more nose up as was the climb into the seat.
3. During a short drive from shop to house there was a prominent sense that the vehicle followed vertical changes along the road with more precision - read stiiffer ride.
4. During that drive fine road roughness was more prominently transferred to the occupant - stiffer ride
3. Don't know how to convey this but there was still an underlying sense of enhanced shock absorber dampening of both - maybe controlled vibration from fine road roughness and minor road up and down movement - I tried to explain, probably did not do very well.

Some measurements, all taken in two different spots using an extended plumb "yard stick" and carpenters level from underside of fender to yard stick all with 50 PSI showing on the air bag remote controller and same water, propane, waste water and load during before and after measurements:
1. Front fender height above ground increased about 4 inches on both sides (This surprised me by being more than I expected)
2. The rear fender height increased by about half of an inch on both sides. (I expected more given 50 PSI in the air bags.)

Followup impressions:
1. Looking at van from the side the front fender LOOKS LOTS HIGHER than my my old recall of that sight picture.
2. I find it odd that the left front was raised a little more than the right front.
3. Our older 2004 Chevy based 190 Popular always was a little lower at the left front than right front when observed by eye ball. I had assumed that the driver weight and water tank under the driver, after 14 years and 200,000 miles had caused the left front springs to sag disproportionately. We shall see if a similar sag seems to occur with the Moog springs on our 2013 over an extended time frame

Aside: I had NAPA "Fleet" front hubs and bearing assemblies installed at the same time as the springs and Air Lift bags, also had NAPA severe duty "Fleet" front rotors and pads installed, plus alignment with specs recommended on this site for our vans after these suspension modifications. OEM front brakes had some "judder", typical compliant about Chevy Roadtreks of that era, and my experience , as well as that of others was that OEM front hub/bearing assemblies had a reputation of early failure for quite a few folks.

Total tab for labor ~$1,000 excluding parts - capable experienced independent local shop that we take our "fleet" to did the work.

More if and when it seems worthwhile to report.

BJ 2004 & 2013 RT 190 Pops
Florida Keys (soon Sun N Fun)
drjones7788@gmail.com

You are the second poster that appears to have gotten way too much lift and more harshness than we are used to hearing about. The other poster had 81004 springs that appeared to be too tall and reported similar results.


The gold standard is just to measure the wheelwell height at the vertical through the wheel center. The lifts with 81004 springs and stock size tires has been quite consistent at 35.5" +/- about 1/4". At 4" of lift, you could be over 37" which is getting to the point of the shocks being too short and topping out which can be noisy and pitchy.


Most of us have found that with 40-60psi in the bags, the van will be slightly nose down, by maybe 1/2 to 1 inch.

 

[booster]

I'm interested in further results as it wears in. I put in moog springs and air lifts. i put my airlifts at 70lbs. Vehicle appears level, using level inside van. Only got 2.5 inch lift in front.

As far as brake rotors, I replaced OEM with PowerStop rotors from Summit Racing. They have grooves to help cool. Reduced chatter to almost nil.

After the lift I got 2-3mpg reduction. Working on upstream O2 sensor replacement. We'll see if it improves. I also noticed a little float, possibly do to more air undercarriage lifting front end? However, the more I drive the more comfortable the ride.

2008 Chevy Express 3500 Pleasure Way Lexor. Similar to RT 190

Good luck with the results.

One thing to remember with doing the spring lift in the front and bags in the rear is that the front spring rate is going to go up and the rear spring rate go down. That change can make the van understeer more and make for larger steering corrections and lower directional stability. The addition of a large rear swaybar with cancel that change out and more, making the van much more responsive to the steering.


If you are getting the feel of float, your shocks could be too low a damping rate for the springs.

 

[Asphalt Addict]

One thing to remember with doing the spring lift in the front and bags in the rear is that the front spring rate is going to go up and the rear spring rate go down. That change can make the van understeer more and make for larger steering corrections and lower directional stability. The addition of a large rear swaybar with cancel that change out and more, making the van much more responsive to the steering.


If you are getting the feel of float, your shocks could be too low a damping rate for the springs.

Thanks Booster, I am running Bilsteins all around. Any suggestions on rear sway bar? Brand, etc.. The PW has the generator back there.

 

[booster]

Thanks Booster, I am running Bilsteins all around. Any suggestions on rear sway bar? Brand, etc.. The PW has the generator back there.

The bar of choice would be a Hellwig if it will fit. It won't fit the Roadtreks with a generator as there is not enough room behind the differential cover. I think you would need about 3" at least as the bar curves up onto the cover area. If that won't fit, you probably could get a Roadmaster bar to fit, as others have gotten them into the Roadtreks with generators. The Roadmaster bars are very expensive though.

 

[mangomike]

Hi
We went to the scales last week ,,,,, fully loaded ,tanks ,bikes ect. 6010 Lbs rear .... just at weight I guess? and 3500 front.

As long as I'm writing,, ,, we have the usual tank sensor problem . We use the "Geo" system to keep the tanks AGAP...But people seem to put in new systems anyway or the other opinion is " you get use to knowing when to pump. Not sure which school I'm in.I did see while doing my research that you replaced yours.
Anyway on my Roadtrek 210 if I open the flushing flap inside the toilet do you literally look right into the holding tank????
Thanks ggain for all your help
Getting pretty comfortable with the van.
michael

 

[booster]

Hi
We went to the scales last week ,,,,, fully loaded ,tanks ,bikes ect. 6010 Lbs rear .... just at weight I guess? and 3500 front.

As long as I'm writing,, ,, we have the usual tank sensor problem . We use the "Geo" system to keep the tanks AGAP...But people seem to put in new systems anyway or the other opinion is " you get use to knowing when to pump. Not sure which school I'm in.I did see while doing my research that you replaced yours.
Anyway on my Roadtrek 210 if I open the flushing flap inside the toilet do you literally look right into the holding tank????
Thanks ggain for all your help
Getting pretty comfortable with the van.
michael

You must have quite a lot weight behind the rear axle hanging off the back or in the rear storage. IIRC, the 210s we have seen weights on would be closer to 3800-4000 in the front when loaded, with some going to the 4300 max. You may want to try to find a way to get some of the weight further forward, as you are pretty tail heavy and if it is overhung on the rear can cause some porpoising. You are also running the rear tires right on max load so would be good to keep and eye on the tire temps with an infrared temp gun (they are cheap).


The two choices you list for tanks would be to replace the sensor system with an external read setup like a Seelevel or similar. They work well, we have had one on ours withtout issue for years.


That other choice is to learn about how long you can go before dumping from experience. Some people are good at that procedure, some not so good, so use you own judgement. You can see somewhat down the toilet, but it is not the most pleasant way:nonono:

 

[Asphalt Addict]

UPDATE: A while back I did 3 things at the same time, not a good idea. I bought new tires, had the suspension lift (Moogs and air bags) and changed spark plugs. My MPG dropped and I didn't know why. Was it suspension lift? Tires? or did I mess up the spark plug install?
I finally found out it was none of the above. It was the upper oxygen sensors. There are two in the Chevy. I had them replaced and my milage went back to normal. Close to 18mpg on a long trip and just under 15mpg all around average. I'm happy again.

 

[rowiebowie]

Always appreciate an update. Thanks.

 

[alaskasail]

Has anyone tried Gabriel Highjacker shocks on the rear? I put a pair on an old Mazda MPV and lifted the rear considerably. I've seriously abused them using the van as a ranch truck and they never have lost pressure. I can raise and lower the van at will. Gabriel also makes a GasSLX shock for heavier applications.

 

[SteveJ-ClassB]

Has anyone tried Gabriel Highjacker shocks on the rear? I put a pair on an old Mazda MPV and lifted the rear considerably. I've seriously abused them using the van as a ranch truck and they never have lost pressure. I can raise and lower the van at will. Gabriel also makes a GasSLX shock for heavier applications.

i installed the Gabriel MAX Control shocks four years ago, about 70k miles on them now. They still work just fine. up front, thinking it is getting near time on the rear for replacements. I did call Gabriel up and explained what I had and the weight involved, they recommended the MAX Control. I don't see the harm in trying the air shocks in the rear but with the angle that the shocks sit at, may not be fully beneficial.

If you do try the air shocks, please post up how they are working out.